Solar LED lamps and lanterns design technical analysis - (AddTime -013-01-30)

As solar photovoltaic technology development and progress, solar battery as a kind of new energy, in the civil aspect first used in lighting lamps and lanterns, solar lighting products due to environmental protection and energy saving of the double advantage. Solar led lighting products are a new generation of green lighting products, its main components including solar photovoltaic cell (PV technology) and semiconductor lighting light source (led). Because of led solar light integrated solar photovoltaic power generation and led solid-state lighting advantages of solar led lighting system, realize a new generation of energy and the perfect combination of new light source. But, in the design of solar lighting lamps and lanterns, involving the light source, solar system, storage battery charging and discharging control many factors, among which a part of any problems will cause defects.

A, first about solar lamps and lanterns composition: Solar photovoltaic power generation technology and 200W led Flood light of perfect combination of both the key lies in with direct current, voltage and can match with each other. So the combination of both don't need solar cells that can produce direct current into alternating current (ac), thus greatly improving the efficiency of the entire lighting system. At the same time, with the help of grid technology or use battery charge and discharge energy, make its advantages more apparent. 1, solar panels
2, charge and discharge controller
3, battery
4, load
5, lamps and lanterns shell Second, the design problems needing attention when using: (in a LED lawn lamp, for example)

1, the characteristics of LED to zener diodes, working voltage change 0, 1 v, working current may change and ma or so. For the sake of safety, general conditions of use series current-limiting resistance, great energy loss is not obviously fit for solar energy lawn lamp, and LED brightness changes with the working voltage. The booster circuit is a good way, also can use simple constant current circuit, a word must be automatic current limiting, otherwise it will damage the LED.
2, general LED peak current fifty to 100 ma, reverse voltage 6 v or so, pay attention to not more than the limit, especially in solar cell reverse connection or battery light, booster circuit peak voltage is too high, probably more than the limit, the damage LED.
3, LED temperature characteristic is bad, rise in temperature 5 ℃, the light fell by 3%, for use in the summer should pay attention to.
4, working voltage discreteness, the same type, same batch LED working voltage has certain difference, should not be used in parallel. Must be parallel use, should consider all flow.
5, super bright white light LED color temperature for 6400 k to 30000 k. At present, the low colour temperature super bright white LED is not to enter the market, so use super bright white light LED manufacturing solar lawn light penetration ability is poor, so in optical design should pay attention to.
6, static super bright white LED to influence, in the installation should have antistatic facility, the workers should wear anti-static wrist. By electrostatic damage was super bright white light LED by eyes may look not to come out, but life will be shorten.
7, system combination should pay attention to light sensors, solar energy lamp need light-operated switch, some designers often use photosensitive resistance to automatically open to turn off the lights, in fact, solar battery itself is a very good photosensitive sensor, and use it to do photosensitive switch, characteristic is better than the photosensitive resistance. For the application of the solar garden light is not big, but to use only a 1, 2 vni - Cd battery solar lawn lamp, solar battery components for the four pieces of solar battery series composition, voltage, weak light voltage lower that day no black voltage has been less than 0, 7 v, cause light-operated switch failure. In this case, as long as add a transistor direct coupling amplifier, can solve the problem. And, according to the battery voltage level control load size, solar energy lamp tends to continuous day of overcast and rainy can hold time demanding, and this increases the cost of the system. We in the continuous day of overcast and rainy battery voltage decreases or reduce 200W led Flood light energy-saving lamps access number, or reduce the solar light daily luminous time, this will reduce the cost of the system.
9, scintillation dimmer, gradually dim the light is energy saving in good way, on one hand it can increase the solar energy lawn lamp irradiation effect, on the other hand, it can by changing the scintillation duty ratio control battery average output current, prolong the system working time, or in the same conditions, can reduce the cost.
10, three color gezer efficient energy-saving lamp switch speed. The problem is very important and it even determines the solar energy lawn lamp life, three color gezer efficient energy-saving lamps start is up to ten to twenty times the starting current, the system under such great current situation will cause the voltage of the dropped substantially, the solar energy lawn lamp can't start or repeated start, lead to the damage.
11, the solar cell is not able to use in the main road lighting. Highway roads lighting have legal illumination requirements, the solar cell conversion efficiency and price, but also not be able to meet this requirement. But in the near future with the various aspects technology level enhancement, solar battery must be applied to highway roads lighting.
12, about the energy storage capacitor, solar battery life in 25 years, common battery life in 2 ~ 3 years, so battery is solar power system is the most weak link. Energy storage capacitor can to a certain extent, solve the problem. Energy storage capacitor life can reach more than ten years, and the control circuit is simple, but expensive price limits its application, has so far been applied only in some traffic lights and the chandelier. With the improvement of technical level, the product price decline, it will be one of the most hope to be solar battery matching ideal energy storage component. To sum up, the solar cell is a huge p-n junction, the solar energy into electricity. LED is another can be converted into electrical energy of the light p-n junction, its conversion efficiency continuously improve, I believe that soon can reach the level of energy-saving lamps, and service life can can reach 100000 hours, this is the real meaning of green lighting.